James Murdoch's departures come as he relocates from London to New York. Photograph: David Cheskin/PA

James Murdoch has stepped down from the boards of the immediate parent companies of the Sun and the Times, one of which is the business named as a defendant in all the phone-hacking civil lawsuits brought against the News of the World.

It emerged on Wednesday that the 38-year-old resigned in September as director of News Group Newspapers – owners of the Sun and the now defunct News of the World, and Times Newspapers Ltd, home to the Times and Sunday Times – as he relocates from London to New York.

News Group Newspapers is the company subject of a string of lawsuits for alleged breaches of privacy stemming from phone hacking, and it is the business unit that anybody wanting to sue either the Sun or News of the World would have to cite as a defendant in a legal case.

News Corporation, the ultimate parent company, said James Murdoch's departure from the boards was essentially a tidying up exercise. It added that the son of Rupert Murdoch remains as executive chairman of News International, which is the operation that runs the company's three British newspapers.

Insiders said that "nobody should read too much into the changes". They noted that James Murdoch remains on the board of a holding company NI Group Ltd and the Times editorial board whose function it is to approve the appointment of new editors of that newspaper.

James Murdoch took over as executive chairman of News International in late 2007, and has been called to give evidence to parliament twice to explain why the company did not find out that phone hacking at the News of the World was more widespread in the period running up to the arrest of Glenn Mulcaire in 2006. Mulcaire carried out hacking on behalf of the newspaper.